Maeshall buenett



\ Q To all 'whomr may concern: f

- rimasi-ms PATENTOFFIGE;

` BURNETT vkn Drin woERi5,-. `i3l'os'roN,"` MASSACHUSETTS.

l MACHINE ron `rnivcrnivcr METAL.

i jfSpecication `of Letters Patent No.`12,712, `dated April` 17, 1855.

Be it known that we, lVIARsHALL` BURNETT and CHRLEsVAN DER WOERD, of Boston, in

" i the county ofSuEolkand State ofMassachusetts, have invented certain new and useful ;`1`Imp`rov,e1nentsin Machines for Punching the f Rivet-Holes in the Plates and Flanges of `Boiler-Heads, &c.; and we do hereby declare "the followingto beta full,` clear, 'and exact description of thesamle,` reference being had ,y to theaccompanying drawings, making a `part thereof, in which-ff" Figure l, represents aside view of the machine, and Fig. 2, represents' avertical longii i parts.

, tudinal sect-ion through the same. p j Similar letters in the `figures `denote like The nature of our invention consists first in giving the barthat carries the punching i tool, a rising and falling motion, parallel to thebed, or bar, that carries the die, so that @the `hole `shall be `punched perfectly square through the plate, which would not bethe i case, ifthe moving bar `were worked from a fixed center.` y y v i To enable others skilled in the art to make scribe the same Vwith reference to the drawings., Y n i 1 A, is the bed or table of the machine, made `fly orbalance `wheel IN, is placed, and a pinion O, to give"motiontjo the machine. On

\ the shaft G`is placeda oog wheel E, and to the crank F, on said shaftis attached one "end of a connecting rod G, the"other end of i said rod being connectedto the `rear end of y ifa leverH, which isl hung, and has its ful- 1crum `at a, in thebrackets I, which are supported on, `or may be cast with the bed A..

` `Alinkorstirrup o, connects the front end of the lever H,`to the front end of the bar J, which carries the punch, and the rear end of i y the said bar J rests ona cam c, arrangedlon 1 a1 shaft d parallel with that C, before de-y 1 i scribed. i

On the shaft which carriesthe cam c is 1 "placed a gear wheel K, having thesame caj `pacity as to circumference and thenumber and use our invention, `we will proceed to de,-4

in any stout substantial manner, and sup?,

of its cogs, as that of E, which meshes intoit, and gives it its motion. The object is to fixed pin e, in the bed, to allow said rear end to rise and fall, as the shape of the cam may admit. f isa spiral spring, which may or may not be required for holding the bar tothe cam, but could only be required in small machines, as the weight of the bar J, of itself will be sufficient to cause it to follow t-he cam. A1 p The camc, and crank F, are so arranged on their respective shafts, as that when the point of the bar J, is'raised up at itsfront end by the lever H, it shall receive a similar rising motion at its rear-end by the cam c, and thus always move parallel with the bed, so as to lbring the punch down square upon the plate to be punched. If the bar J, moved "from a fixed center, as the lever H does, the hole that would be punched by it,

- leave a fin or rough place, at one side of the hole, and the holes of the plates when brought opposite to each other would not perfectly match. But by moving the punch and bar parallel with the bed such contingency is entirely obviated.

On the front of the bed A, and bar J, are placed two nibs m m', projecting from the faces of both the bed and bar, and extending out beyond the points of each, as seen in the drawing. The upper nib m, carries the punch n, and the lower one m the die 0. These nibs are sol extended out beyond t-he points of the bed and bar, for the purpose of punching rivet holes in the flanges turned elsewhere in the boiler head, than on its pe- `riphery,`as for instance the flanges of the flue holes. An `ordinary flange on the periphery may be readily punched by a punch and die in the ends of the bar and bed alone,

"but by the use of the nibs or prolonged portherefore an important feature in our machine, and one which adds materially to its value.

Having thus fully described the nature of our invention, what We claim therein as new and desire to secure by Letters Patent, is-

So combining the punching bar, With a vbrating lever at one end, and a cam at the other end of it, as that it shall always rise and fall, in a plane parallel t0 the bed of the 10 machine, substantially as described.

MARSHALL BURNETT. CHS. VAN DER WOERD. VVitnesses:

Z. E. COFFIN, I. D. SPAULDIYNG. 

